Project Summary The overarching goal of the current proposal is to uncover the neural mechanisms that underlie figure-ground segregation, an important component of natural scene interpretation, focusing on the role of the primary visual cortex (V1) and its dynamic interactions with higher visual cortical areas. Specifically, we will measure how V1 responds to a wide range of backgrounds, including artificial and naturalistic textures, with and without occluding targets, and develop computational encoding models that would allow one to predict V1 population responses at multiple biologically-relevant spatial scales to arbitrary figures and backgrounds (Aim 1). In Aim 2 we will study the role of V1 in figure-ground discrimination by measuring and perturbing V1 population responses while animals detect a camouflaged target that occludes a background of the same texture family. These experiments will be used to distinguish between different candidate decoding models that describe how single-trial V1 population responses lead to behavior in the task. An important goal would be to test whether V1 plays an active role in the segmentation computation. The alternative is that V1 provides the feedforward input to a segmentation computation that occurs downstream, and receives top-down figure-ground signals only after the segmentation had been completed. Overall, the proposed experiments will lead to a deeper understanding of the role of V1 in fundamental mid-level visual computations and will serve as an important step toward a quantitative understanding of the representation of complex natural scenes by populations of neurons in V1.